Packaging systems that blow mold, fill, and seal containers such as bottles, bags, and the like, enjoy widespread commercial acceptance because of ease of fabrication and reduced labor costs. Moreover, such a packaging system obviates the need for costly auxiliary equipment that cleans and handles empty containers, fills the containers, and subsequently seals the filled containers. A packaging system of the foregoing type is disclosed in U.S. Pat. No. Re. 27,155 to Hansen.
Since the complete filling cycle for a container takes place in an enclosed environment when the aforementioned form, fill, and seal packaging system is employed, this system is well-suited for sterile and aseptic packaging of parenteral solutions and the like substances. However, for such solutions it is desirable to provide a container having an access aperture of controlled dimensions that can receive a draining spike without undesirable leaking when it is desired to drain the container contents. For non-collapsible containers it is also desirable to provide a venting aperture provided with an outwardly projecting stem or boss of controlled outside dimensions so that an air filter can be conveniently mounted thereon when the container contents is drained.
Heretofore, it has not been possible to consistently attain the requisite dimensional control in a unitary blow-molded container, particularly for internal dimensions. The present invention, however, provides unitary dispensing containers having access apertures and unitary, externally projecting members of predetermined, relatively closely controllable dimensions.
Heretofore, a single mandrel (containing a gas blowing nozzle or port and a filling liquid discharge nozzle or port) has been used for both blow molding a container and then filling the container. Typically, the mandrel is incorporated in an apparatus for automatically and repeatedly blow molding and filling containers seriatim.
It has been found, however, that in some high-speed production runs, drops of the liquid product with which the containers are filled may cling to the liquid discharge nozzle or other parts of the mandrel after a container is filled with the liquid. When the next container is blow molded with the same mandrel, some of the drops of liquid on the mandrel may fall off, or be blown off, of the mandrel and into the container during its formation from hot, soft thermoplastic material in the blow molding step. This can lead to cratering or pitting of the thermoplastic material that forms the inside surface of the blow-molded container. Accordingly, it would be desirable to provide a method for blow molding and then filling containers in a manner that substantially eliminates such cratering or pitting problems.